PNEUMOCYSTIS-CARINII PNEUMONIA IN A TERM NEWBORN-INFANT WITH A TRANSIENTLY DEPRESSED T-LYMPHOCYTE COUNT, PRIMARILY OF CELLS CARRYING THE CD4 ANTIGEN

A term infant without infection by human immunodeficiency virus had pn eumocystis pneumonia at 17 days of life. Initial counts of T lymphocyt es carrying the CD4 antigen were approximately 50% of the lower limits of normal; later the counts of T lymphocytes carrying the CD3 and CD8 antigens decreased as well. By 7 weeks after resolution of the pneumo nia, CD3+, CD4+ and CD8+ cell counts hod returned to normal. These obs ervations suggest that a primary transient deficiency of T cell produc tion or maturation, especially involving CD4+ cells, may occur in othe rwise normal newborn infants.